Stereoscopic viewers have been known for quite some time. However, today's commercially available stereoscopic viewers are adapted only for use with individual slides or photographs, not for continuous stereoscopic filmstrips, such as 35 mm rolls. Nonetheless, the concept of continuous stereoscopic filmstrip viewers is described in a number of U.S. Patents. See, for example, U.S. Pat. Nos. 2,573,543, 2,590,260, 2,814,966, 3,414,346, 3,473,870, 4,026,636, 4,142,778 and 4,256,367.
However, none of these patents describe a machine or apparatus which allows for hand-free continuous stereoscopic filmstrip viewing, simultaneously hearing a related audio tape, in a manner which allows the apparatus to be used as a versatile teaching machine.